Contraceptives are categorized into long-acting, short-acting and emergency contraceptives. Long-acting contraceptives are taken on a fixed day of the month, short-acting contraceptives are taken every day, and emergency contraceptives are taken within 72 hours after intercourse. The use of contraceptives need to consult a professional, pay attention to adverse reactions, there are contraindications for people should not be used. 1. Long-acting contraceptives: mainly compound ethinyl estradiol monthly tablets, compound 18 methyl ethinyl ketol monthly tablets, etc., the first time you need to take in the fifth day after menstruation, 10 days, respectively, or the fifth day of menstruation, followed by an interval of 20 days to take again, and then later on every month to choose a day to take a fixed dose, each time a piece of it can be. 2. Short-acting contraceptives: these drugs include drospirenone ethinyl estradiol tablets, deoxyprogesterone ethinyl estradiol tablets, etc., most of which need to be taken every day, from the first day of menstruation to the fifth day of the period to start, take a cycle of consecutively, such as coitus during the period need to do a good job of contraception. 3. Emergency contraceptive pills: levonorgestrel tablets and other drugs, need to be taken within 72 hours of intercourse, and then the interval of 12 hours and then take 1 time, the sooner the drug, the better the contraceptive effect. However, the side effects of this type of drug are large, so it should be taken at most once a month, not more than 3 times a year, so as not to cause discomfort. Contraceptive pills may cause adverse reactions such as early or delayed menstruation in the same month, vomiting, etc.; in addition, contraceptive pills should not be used by people who are suspected to be pregnant, during pregnancy, cancer of the reproductive organs, abnormal liver function, heart attack, cerebral thrombosis, etc. It is recommended that you consult with a professional before using the medication.